lkml.org 
[lkml]   [2020]   [Jul]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 12/18] mips: csum_and_copy_{to,from}_user() are never called under KERNEL_DS
    Date
    From: Al Viro <viro@zeniv.linux.org.uk>

    they are only called for iovec-backed iov_iter and under KERNEL_DS an
    attempt to create such a beast will yield a kvec-backed one.

    Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
    ---
    arch/mips/include/asm/checksum.h | 32 +++++++-------------------------
    1 file changed, 7 insertions(+), 25 deletions(-)

    diff --git a/arch/mips/include/asm/checksum.h b/arch/mips/include/asm/checksum.h
    index 1e5558f90126..7a5c97c5d705 100644
    --- a/arch/mips/include/asm/checksum.h
    +++ b/arch/mips/include/asm/checksum.h
    @@ -41,22 +41,6 @@ __wsum __csum_partial_copy_from_user(const void *src, void *dst,
    int len, __wsum sum, int *err_ptr);
    __wsum __csum_partial_copy_to_user(const void *src, void *dst,
    int len, __wsum sum, int *err_ptr);
    -/*
    - * this is a new version of the above that records errors it finds in *errp,
    - * but continues and zeros the rest of the buffer.
    - */
    -static inline
    -__wsum csum_partial_copy_from_user(const void __user *src, void *dst, int len,
    - __wsum sum, int *err_ptr)
    -{
    - might_fault();
    - if (uaccess_kernel())
    - return __csum_partial_copy_kernel((__force void *)src, dst,
    - len, sum, err_ptr);
    - else
    - return __csum_partial_copy_from_user((__force void *)src, dst,
    - len, sum, err_ptr);
    -}

    #define _HAVE_ARCH_COPY_AND_CSUM_FROM_USER
    static inline
    @@ -65,9 +49,12 @@ __wsum csum_and_copy_from_user(const void __user *src, void *dst, int len)
    __wsum sum = ~0U;
    int err = 0;

    + might_fault();
    +
    if (!access_ok(src, len))
    return 0;
    - sum = csum_partial_copy_from_user(src, dst, len, sum, &err);
    + sum = __csum_partial_copy_from_user((__force void *)src, dst,
    + len, sum, &err);
    return err ? 0 : sum;
    }

    @@ -84,14 +71,9 @@ __wsum csum_and_copy_to_user(const void *src, void __user *dst, int len)
    might_fault();
    if (!access_ok(dst, len))
    return 0;
    - if (uaccess_kernel())
    - sum = __csum_partial_copy_kernel(src,
    - (__force void *)dst,
    - len, sum, &err);
    - else
    - sum = __csum_partial_copy_to_user(src,
    - (__force void *)dst,
    - len, sum, &err);
    + sum = __csum_partial_copy_to_user(src,
    + (__force void *)dst,
    + len, sum, &err);
    return err ? 0 : sum;
    }

    --
    2.11.0
    \
     
     \ /
      Last update: 2020-07-21 22:27    [W:4.166 / U:0.268 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site